Do pastes made on Ubuntu Pastebin Service get deleted?

It took 8 years for Pastebin.com to surpass 10 million "Active" pastes (not spam or expired pastes).1 Less than a year later the owners of Pastebin.com tweeted that they had already surpassed the 20 million active pastes mark.^{Tech Crunch}

The maximum size a paste can be is 512 kilobytes (0.5 megabytes). This should be enough for almost any script, and it prevents people from jamming our servers. PRO members are allowed to create pastes up to 10 megabytes.

As far as pastebin.ubuntu.com, from what I found out from my pastes that it's probably a six to nine month windows. Because anything that I pasted that's less that nine months old, I can still find, but anything over a year I'm not able to find.

I hope that answers your question.